This film was the first Japanese science fiction film which had the original Japanese cast and crew listed on the posters and other advertising material in the United States.
The exterior of the "Science Center" was actually Japan's National Sports Center that was built for the upcoming Tokyo Olympiad. The structure was new and had a slightly futuristic look.
In the movie, a reference is made to the "Sea of Rains". This is the Mare Imbrium, the second-largest "sea" on the moon, and one of the largest impact craters in the solar system. In the "Man in the Moon" image of Western folklore, Mare Imbrium forms the man's right eye.
Many sources list the running time of the U.S. version as 74 minutes. This error was originally generated by the U.S. distributor, Columbia Pictures. The 74-minute running time is actually that of its theatrical co-feature, 12 to the Moon (1960).
In the final battle sequence that takes place over Tokyo, one of the landmarks destroyed by the mother ship was Tokyo's huge Cinerama theatre.